Dotted line attachment for drafting machines



2,746,157 Patented May 22, 1956 DOTTED LINE ATTACHMENT FORDRAFTING. MACHINES ForrestL. LangfortLLos Angeies, (Iaiif. Application December-21, 1953, Serial No. 399,448

11 Claims. (Cl. 33-174) My invention relates generally to drawing instruments and'more particularly to aternplate for drawing dotted lines and the like and means for securing such a template to the scale of a'eonventional drafting machine.

While templates have'in the past been designed for the purpose'ofdrawing-dotted lines, dot dash lines, and thelike, such devices. consisting in a thin apertured sheet interposed between the drawing surface and a ruling straight edge prior devices of the type described. have not been completely successful for several reasons. For one thing, a template which is thin enough to permit the useof a pencilpassing over it from aperture to aperture drawing a dotted line, must be reinforced to. protect the same against damage by bending, warping and the like. Such reinforcement adds to the costof manu: facturing the template and interferes with its use in. con: junction with a a conventional straightedge.

Another disadvantage of previouszdevices isthatno.

successfuhmeans has beenprovided'heretofore, by which such" a:ternplate may be: supported in connection with. a

straightedgeof'a conventional drafting machine soas to assure :accurate placement ofthe. dotted'line drawn:with the template.

With a view'tdovercoming the disadvantages above stated, .it'is' atmajor object offthe preseutinvention to pro: vid'e a templateattachrnent for. use with straight. edges andtscales. inzconventional drafting machines, which. isrso desi ned' and constructedfthat the orientation and positionrof -thedine. is' determined in. the usual; manner by appropriate. placing .of' the :draftingmachine, the template serving-merely. to. interrupt-the line. and providethe. desired dots or dashes therein.

Another objectof the. present-invention; is to provide a template attachment ofthe-class described which. may berreadily attached to; conventionali drafting machines without modification of the same, and. may be-yreadily removedzfor cleaningon in theeventthat it is; desired to use the machine without the template.

Still another object ofqthe invention. is:to provide an attachment of the' class described which is so securedto the scale. with which'it is. used, as to protect thetemplate' against bending, Warpingor'the like, thus making it; possible to make the. templateextremelythin and thereby increase itseffectiveness, when used with-a pencil.

Yet: another object'of theinvention is to provide an attachment: of the classdescn'bed inwhich the template maybe-snapped .into, .andout of operative position, being at-alhtimes carried by the-scale. to which it is attached in readiness; for use when desired.

Yeta further. object of the invention is to provide an attachment of the classdescribed. in which'the: template has various types. of aperture groupings, thus providing for eitherv dotted OI.-dOI-d8Sh-.'1ID8S or the like as-may be needed. andlin. which any selectedqaperture group may; be snappedinto. operative. position-adjacent the fiducial edge of the rulingscale.

The foregoing. and additional. objects and. advantages of the inventionwilllbe. apparentirom. the-following detailed description of a presently'preferred embodimentthereof, considerationbeing given also to the attached drawing in which:

Figure 1 is a fragmentary plan viewof a conventional,

two-scale draftingmachine in'which-each of'the ruling scales is provided with a template attachment constructed in accordance with the presentinvention, the attachments being shownin. retractedon non-use position;

Figure 2 is an enlarged, fragmentary, plan view of.one. endrof horizontal scale .of the device shown in Figure,

l, but with the templatezin oneextended. position-for the purpose of drawing;a dot'-;dash, line;

Figure 3. is an elevationallsection taken on 'line 3-=3':

in Figure 2;

Figure 4-is an enlarged :plan. view, similar; to .Figureiil, but'with the template advanced tea a dotted line;

Figure '5' is an-elevationalyiew taken on the. line. 5.'5

in Figure'4; and- Figure -6=isan elevational-section" similar to Figure-5 showing, modified attachment means.

In the drawings, a conventional drafting machine is indicated by thereference characterv lil- The drafting machine iilrincludesthe .usualpantograph arm 11;carrying a bracketafi ;t0 which? is;.-secured a horizontal ruling; scale..13 anda-yertical ruling scale 14; Thescales Hand- 14. are secured to, the bracket 12- by means of: convene. tional-clip..members 15.each of which is receivedinzarcomplemental wedge-shaped slot in the under sidevofthe.

bracketll. Clip members, 15*31'6 :mounted at. both: ends of.the..scales 13.. and l4.so.the samemaybereversed-tobring the desired. ruling-edge into-operative position.

The drafting machinelil-is constructed. in. all, respects in conventional. mannerand details .of the devicev not.

importanttto. thepresent. inventionarenot set forth at length herein.

The, attachment of" the :present invention comprises, a template. 16- and. a, pair. of. spring mounting. arms 17 secured. to vthelernplatel6 andarrangedto engage. the'upper surface.ofrthe respective scale.13. or 14 to which-the tern plate is to be attached. In the 'pr esentillustrationteach.

scale.is.providedwitha,template. In addition; to-engaging the uppensurfacesof the scale 13.-or'14,'the spring. arms 17 are laterally biased; to engage attachment lugs 18. secured .totheupper. surface of the scale as will bedescribed inmore. detaihhereinafter;

of "005; tov .OlOinch in. thickness.

fornra dot-dash; or center linesuch as that indicated at 21. in Figure 2, and the apertures; in the row Mi -being; designed. toform what is-generally termed a. dottedline such as-is shown-at-22 in Figure 4;

The rear edge of the template 16' is'bent upwardly;

to forma flange 23 ,which is reinforced by a down-turned,

relatively deep channel member 24 which is;crimped1over' The flange,

the flange23 asrcanbeseen best in Figure-3; 23 stifi'ens thetemplateld-andi additionally receivessthe. arms 17 as-rwill bedescribed.

The 'arrns17areadjustably fastened to thevtemplate 16. by means'of-saddle members 25 secured totherearward:

endsof the arms-.17 as by-brazing indicatedatZdinFig: ure 3.

be seen thatthearmsmay be moved along the flangef23 to anydesired positionthereonzthen by slidingthegsaddle member. 25. along the. channel- 24- andfastened atsuch. position, by tightening. the settscrew 27.v

position; for making Eachsaddle Inember-ZS'is in-turn made fast to. the. reinforced flange 23-44. by-meaus; of asetascrew 27 threaded into the back of. the saddle member 25; Itwill;

e The forward ends of the arms 17 are bent to form a series of crenulations or depressions 30, 31 and 32 in the side of eachof the arms 17. It is desirable to index the template to various positions at which one or another of the aperture rows 19 or 20 is in operative position. To this end the notches 30, 31 and 32 are accurately spaced along the arm so that the longitudinal distance between given notches is substantially the same in each The accurate indexing of the template 16 whereby to place the desired aperture row in alignment with the edge of the scale, is accomplished by engaging the appropriate notches 30, 31, or 32 of each arm 17 with the downturned ends 33 of the attachment lugs 18.

It will be noted that in the preferred embodiment shown in Figure 2 each'of the attachment lugs 18 is secured on top of one of the clips 15 using the-conventional attachment screw 15a of the latter. Adjustment of the device so as to place the aperture rows in exact parallelism with the front edge of the scale is accomplished by loosening the screw holding one of the lugs 18 and rotating the same slightly on its screw whereby to move one of the arms 17 forwardly or rearwardly thus swinging the template 16 into the aforesaid parallel position. a

It will be noted that due to the accurate spacing of the notches 30, 31 and 32 in the arms 17, once the template has been adjusted into parallelism as above noted, and aligned with the 'scale edge, the template will always return to the same position when an appropriate pair of notches in the two arms are engaged with the ends 33 of the respective lugs 18.

The outermost notch 32 in each of the arms 17 is spaced outwardly a greater distance than the distance between other notches whereby to provide a detent for holding the template in a retracted position completely withdrawn under the scale. Furthermore, it will be noted that that portion of the arm extending beyond the notch 32 is inclined inwardly so as to prevent the template from being inadvertently pulled off of the scale, when it is retracted to a position under the scale. However, the resiliency of the arm 17 is such that by exerting more force than needed to retract the template 16, it may be pulled entirely off the scale.

An alternative mounting arrangement is illustrated in Figure 6 wherein it will be seen that the lug 18 is inverted from its position in the previous embodiment and the arm 17 instead of engaging the bent over end 33 of the lug 18, engages a blunt nose-like protrusion 34 at the opposite end of the lug 18. Thus, the arm 17 is passed under the clip 15 into a space between the clip and the scale 13. This latter arrangement is provided for certain types of drafting machines in which the clip 15 is spaced above the upper surface of the scale as illustrated in Figure 6.

In the embodiment shown in Figure 6, similar adjustment into parallelism may be accomplished by loosening the screw 15a and swinging the lug 18 about the screw by means of the end 33 which now projects upwardly due'to the inversion of the clip 18. I

7 It will be noted that in both of the embodiments shown herein,.the arm, in addition to engaging either the nose 34 or the downturned end 33, projects through a transverse gnide opening and is held down against the upper surface of the scale either by the overlying lug 18 or by the overlying clip 15. Each arm is, thus, prevented from slipping out of its aligning engagement. Additionally, thespring bias of each of the arms 17 is such as to bear downwardly on the upper surface of the scale thus causing the template 16 to be pressed upwardly into intimate contact with the under surface of the scale.

While the embodiment in Figure 1 is shown with a separate template attached to each of the two scales, it will be realized that due to the accurate spacing of the notches 30, 31 and 32, and the arms 17, and due to the mode of adjustment of the lugs 18, a single template would suiiice for most operations and could be transferred between the scales 13 and 14 at will, by the simple expedient of moving the same from the back of the scale in each case and replacing it by springing out the arms 17 manually and inserting them into the appropriate positions of engagement as illustrated in the drawings.

While the forms of the device shown and described herein are fully capable of achieving the objects and providing the advantages hereinbefore stated, it will be realized that they are capable of some modification without departure from the spirit of the invention. For this reason I do not mean to be limited to the forms shown and described, but rather to the scope of the appended claims.

I claim:

1. In combination with a draftsmans rule having a front ruling edge formed therein: a relatively thin template having a row of apertures adjacent and substantially parallel to a forward edge thereof adapted when said template is in a first position to be completely withdrawn under said rule and when said template is in a second position to underlie said ruling edge to modify a line drawn therealong, said template being substantially wider than said rule whereby the rearward edge of said template lies behind said rule in either of said positions; resilient means secured to said rearward edge of said template and projecting forwardly across the top of said rule, said last means being spring biased downwardly to hold said template slidably against the under side of said rule; and guide means secured to the upper surface of said rule to slidably engage said resilient means whereby to constrain movement of said template between said first and second positions to translatory motion in a direction substantially transverse to said ruling edge.

2. In combination'with a draftsmans rule having a front ruling edge formed therein: a relatively thin template having a row of apertures adjacent and substantially parallel to a forward edge thereof adapted when said template is in a first position to be completely withdrawn under said rule and when said template is in a second position to underlie said ruling edge to modify a line drawn therealong, said template being substantially wider than said rule whereby the rearward edge of said template lies behind said rule in either of said positions; a pair of resilient arms each secured to saidrearward edge of said template and projecting forwardly across the top of said rule, said arms being spring'biased downwardly to hold said template slidably against the other side of said rule; and a pair of guide members secured to the upper surface of said rule, each adapted to slidably engage a respective one of said arms whereby to constrain movement of said template between said first and second posi tions to translatory motion in a direction substantially transverse to said ruled edge.

3. In combination with a draftsmans rule having a front ruling edge formed therein: a relatively thin template having a row of apertures adjacent and substantially parallel to a forward edge thereof adapted when said template is in a first position to be completely withdrawn under said rule and when said template is in a second position to underlie said ruling edge to modify a line drawn therealong, said template being substantially wider than said rule whereby the rearward edge of said template lies behind said rule in either of said positions; a spaced pair of guide members secured to the upper surface of said rule; a pair of resilient arms secured to said rearward edge of said template and projecting forwardly across the top of said rule, each adjacent a respective one of said guide members, said arms being biased downwardly to hold said template slidably against the under side of said rule, and said arms being biased laterally in opposite directions whereby to frictionally engage said guide members to retain said template in any adjusted position thereof.

4. In combination with a draftsmans rule having a zg'wien 57:

front ruling-. edgenformedx'therein; a relatively thin tem under said rule :andfwhen said .ternplate isin a second positionitozunderliezsaid;rulingedge-to modify a line drawn :therealon g, said :ternplateabein g substantially wider than said rule :whereby :the rearward edge of said template liesb'ehind'saidirule inseither ofsaid positions; a spaced pair. of guide rnembers secured itothe upper surface of said rule; a pair of resilientarms secured to said rearward edge of said template and projecting ,forwardlyracross the top of sai'd'rule; each adjacent'a respective one of said guide members,. said armsbeingtbiased downwardly to hold. said template slidably against the under side of said rule,.,and.said arms being biased laterally in" opposite directions whereby to frictionally engage said guide members to retain said template in any adjusted position thereof, said arms having lateral crenulations therein engaged with said guide members wherebyzto index said template with respect to said rule in various positions of the former.

5. In combination with a draftsmans rule having a front ruling edge formed therein; a relatively thin template having a row of apertures adjacent and substantially parallel to a forward edge thereof adapted when said template is in a first position to be completely withdrawn under said rule and when said template is in a second position to underlie said ruling edge to modify a line drawn therealong, said template being substantially wider than said rule whereby the rearward edge of said template lies behind said rule in either of said positions; a pair of guide members secured to the upper surface of said rule; a pair of resilient arms secured to said rear ward edge of said template and projecting forwardly across the top of said rule, each adjacent a respective one of said guide members, said arms being biased downwardly to hold said template slidably against the under side of said rule, and said arms being biased laterally in opposite directions whereby to frictionally engage said guide members to retain said template in any adjusted position thereof, said arms each having a terminal portion bent toward said guide member engaged therewith to yieldably resist withdrawal of said arms from said guide members.

6. A draftsmans interrupted line template attachment for rules comprising in combination: a relatively thin metal template adapted to be placed on a drawing surface under a rule with a forward portion of said template projecting beyond the ruling edge of said rule, said template having a plurality of rows of apertures adjacent a forward edge thereof and parallel to said edge, positioned and adapted to selectively underlie said ruling edge whereby to interrupt a line drawn on said drawing surface against said ruling edge; an upturned longitudinal flange formed on the rearward edge of said template and positioned to lie to the rear of said rule with said template projecting as aforesaid; a pair of saddle members slidably positioned on said flange, and having means to secure the same to said flange at any adjusted position thereof; a pair of resilient arms, one secured to each saddle member and projecting forwardly across the top surface of said rule, said arms being biased downwardly to hold said template against the under surface of said rule and said arms each having a plurality of notches formed in a side thereof, the spacing of notches along one arm corresponding to that along the other and one of said groups of notches facing in the opposite direction from the other group; a pair of lugs fixed on the upper surface of said scale, one adjacent each arm, said lugs each having a detent projection positioned and adapted to engage notches in a respective arm whereby to yieldably retain said template in one of a plurality of positions in which one or another of said rows of apertures underlies the forward edge of said rule, or the forward edge of said template is withdrawn under said rule.

7'. A draftsrnan s attachment: for: use witha--rule=hav'-' ing a frontrulihgedge: a-relatively thiri ternplate having a row of openings therein adjacent to; andalongone edge-thereof, said row being adapted to be placed under said'ruling edge of said rule to'modify a linedrawn against said edge, said template being adapted when in -a first positiorrto have said forward edgethereof completely withdrawn-under saidrule and'when ina second position to have said row of openings underlying said ruling edge as aforesaid, and said 1 template being of substantial width as compared to the width of-said rule; a pair of arms secured to a rearward-edge of-said template, said'arms extendi'ngaround therearwardedge of said ruler and projecting forwardl'y above, and spaced arms whereby to. constrain.movement;of=said.template: between said first and secondipositionsto.translatory' motion in a. direction substantially; transverse: to" said J ruling edge.

8. A draftsmans attachment for use with a rule having a front ruling edge: a relatively thin template having a row of openings therein adjacent to and along one edge thereof, said row being adapted to be placed under said ruling edge of said rule to modify a line drawn against said edge, said template being adapted when in a first position to have said forward edge thereof completely withdrawn under said rule and when in a second position to have said row of openings underlying said ruling edge as aforesaid, and said template being of substantial width as compared to the width of said rule; a pair of arms secured to a rearward edge of said template, said arms extending around the rearward edge of said ruler and projecting forwardly above, and spaced from said template to slidably engage the top surface of said rule to hold said template slidably against the underside thereof; guide means adapted to be secured to the top surface of said rule to slidably engage said arms whereby to constrain movement of said template between said first and second positions to translatory motion in a direction substantially transverse to said ruling edge; and stop means formed in said arms and engageable with said guide means to limit said movement selectively in either of said positions of said template.

9. A draftsmans attachment for use with a rule having a front ruling edge: a relatively thin template having a row of openings therein adjacent to and along one edge thereof, said row being adapted to be placed under said ruling edge of said rule to modify a line drawn against said edge, said template being adapted when in a first position to have said forward edge thereof completely withdrawn under said rule and when in a second position to have said row of openings underlying said ruling edge as aforesaid, and said template being of substantial width as compared to the width of said rule; a pair of resilient arms each secured to a rearward edge of said template, said arms extending around the rearward edge of said ruler and projecting forwardly above the same and spaced therefrom, said arms being spring biased downwardly to engage the top surface of said rule and to hold said template slidably against the underside of said rule; and a pair of guide members adapted to be secured to the upper surface of said rule, and each adapted to slidably engage a respective one of said arms whereby to constrain movement of said template between said first and second positions to translatory motion in a direction substantially transverse to said ruling edge.

10. A draftsmans attachment of the class described for use on a rule having a front ruling edge: a relatively thin template having a row of openings therein adapted to be placed under said ruling edge to modify a line drawn against said edge; a pair of spaced parallel elongate members each secured at one of its ends to said template adjacent an edge thereof, said members extending substantially at right angles to said row of apertures inwardly across said template and spaced above the same by substantially the thickness of a rule on which said attachment is to be used, said members upon slight horizontal pressure being adapted to slidably engage the top surface of said rule to movably retain said template against the underside thereof; stop means adapted to be secured to the top surface of said rule adjacent said members; an index means formed in said members and engageable with said stop means to limit motion of said template to either of two selective positions, in one of which said row of openings underlies said ruling edge and in the other of which the forward edge of said template is entirely Withdrawn under said rule to leave said ruling edge unobstructed.

11. A draftsmans rule attachment of the class described, comprising: a relatively thin template having a row of apertures therein adapted to be placed under the ruling edge of a draftsmans scale to modify a line drawn against said edge; a plurality of resilient members secured to a rearward edge of said template extending for w wardly and adapted to be slidably engaged with a top surface of said scale to hold said template upwardly against the under surface of said scale; and indexing means formed in said movable resilient members, adapted to contact fixed stops on said upper surface of said rule to position said template in its desired parallel relation to the front edge of said rule and at the same time to guide said template in its movement from said extended position beyond the front edge of the rule, to its retracted position in which said ruling edge is unobstructed, and vice versa.

References Cited in the file of this patent UNITED STATES PATENTS 965,945 Roman Aug. 2, 1910 1,293,313 Berkoff Feb. 4, 1919 1,979,724 Asencio Nov. 6, 1934 FOREIGN PATENTS 5,821 Great Britain 1908 739,928 France Jan. 19, 1933 

